In copper pyrometallury industry, one method is producing blister copper indirectly from sulfide copper concentrate, which generally comprises two steps: first the sulfide copper concentrate is subjected to desulfurization and iron removal and smelting to obtain high-grade copper matte; and then the resulting copper matte is further subjected to desulfurization and iron removal and converting to give blister copper. Another method is producing blister copper directly from copper concentrate, which is adopted in practical production by Olympic Dam smeltery in Australia, Glogow smeltery in Poland, and KCM smeltery in Zambia. The blister copper produced by these copper smelting methods generally has a copper content of 98.5% by weight. However, these methods have a common feature that the slag resulted from production contains Cu2O and Fe3O4 in a relatively large amount. In general, the slag contains 10% to 20% by weight of copper, and 30% to 50% by weight of Fe3O4, which leads to waste of a large amount of resources.